/*
 *  Copyright 2004 Clinton Begin
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */
package com.ibatis.sqlmap.engine.mapping.sql.dynamic.elements;

import java.io.PrintWriter;
import java.io.StringWriter;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;

import com.ibatis.sqlmap.engine.mapping.parameter.ParameterMapping;

public class SqlTagContext {

    private StringWriter sw;
    private PrintWriter out;

    private HashMap attributes;

    private LinkedList removeFirstPrependStack;
    private LinkedList iterateContextStack;

    private ArrayList parameterMappings = new ArrayList();

    public SqlTagContext() {
        sw = new StringWriter();
        out = new PrintWriter(sw);
        attributes = new HashMap();
        removeFirstPrependStack = new LinkedList();
        iterateContextStack = new LinkedList();
    }

    public PrintWriter getWriter() {
        return out;
    }

    public String getBodyText() {
        out.flush();
        return sw.getBuffer().toString();
    }

    public void setAttribute(Object key, Object value) {
        attributes.put(key, value);
    }

    public Object getAttribute(Object key) {
        return attributes.get(key);
    }

    public void addParameterMapping(ParameterMapping mapping) {
        parameterMappings.add(mapping);
    }

    public List getParameterMappings() {
        return parameterMappings;
    }

    public boolean isEmptyRemoveFirtPrepend() {
        return removeFirstPrependStack.size() <= 0;
    }

    /**
     * examine the value of the top RemoveFirstPrependMarker object on the stack.
     * 
     * @return was the first prepend removed
     */
    public boolean peekRemoveFirstPrependMarker(SqlTag sqlTag) {

        RemoveFirstPrependMarker removeFirstPrepend = (RemoveFirstPrependMarker) removeFirstPrependStack.get(1);

        return removeFirstPrepend.isRemoveFirstPrepend();
    }

    /**
     * pop the first RemoveFirstPrependMarker once the recursion is on it's way out
     * of the recursion loop and return it's internal value.
     *
     * @param tag
     */
    public void popRemoveFirstPrependMarker(SqlTag tag) {

        RemoveFirstPrependMarker removeFirstPrepend = (RemoveFirstPrependMarker) removeFirstPrependStack.getFirst();

        if (tag == removeFirstPrepend.getSqlTag()) {
            removeFirstPrependStack.removeFirst();
        }
    }

    /**
     * push a new RemoveFirstPrependMarker object with the specified internal state
     * 
     * @param tag
     */
    public void pushRemoveFirstPrependMarker(SqlTag tag) {

        if (tag.getHandler() instanceof DynamicTagHandler) {
            // this was added to retain default behavior
            if (tag.isPrependAvailable()) {
                removeFirstPrependStack.addFirst(new RemoveFirstPrependMarker(tag, true));
            } else {
                removeFirstPrependStack.addFirst(new RemoveFirstPrependMarker(tag, false));
            }
        } else if ("true".equals(tag.getRemoveFirstPrepend()) || "iterate".equals(tag.getRemoveFirstPrepend())) {
            // you must be specific about the removal otherwise it
            // will function as ibatis has always functioned and add
            // the prepend
            removeFirstPrependStack.addFirst(new RemoveFirstPrependMarker(tag, true));
        } else if (!tag.isPrependAvailable() && !"true".equals(tag.getRemoveFirstPrepend())
                && !"iterate".equals(tag.getRemoveFirstPrepend()) && tag.getParent() != null) {
            // if no prepend or removeFirstPrepend is specified 
            // we need to look to the parent tag for default values
            if ("true".equals(tag.getParent().getRemoveFirstPrepend())
                    || "iterate".equals(tag.getParent().getRemoveFirstPrepend())) {
                removeFirstPrependStack.addFirst(new RemoveFirstPrependMarker(tag, true));
            }
        } else {
            removeFirstPrependStack.addFirst(new RemoveFirstPrependMarker(tag, false));
        }

    }

    /**
     * set a new internal state for top RemoveFirstPrependMarker object
     *
     */
    public void disableRemoveFirstPrependMarker() {
        ((RemoveFirstPrependMarker) removeFirstPrependStack.get(1)).setRemoveFirstPrepend(false);
    }

    public void reEnableRemoveFirstPrependMarker() {
        ((RemoveFirstPrependMarker) removeFirstPrependStack.get(0)).setRemoveFirstPrepend(true);
    }

    /**
     * iterate context is stored here for nested dynamic tags in
     * the body of the iterate tag
     * 
     * @param iterateContext
     */
    public void pushIterateContext(IterateContext iterateContext) {
        iterateContextStack.addFirst(iterateContext);
    }

    /**
     * iterate context is removed here from the stack when iterate tag is finished being
     * processed
     * 
     * @return the top element of the context stack
     */
    public IterateContext popIterateContext() {
        IterateContext retVal = null;
        if (!iterateContextStack.isEmpty()) {
            retVal = (IterateContext) iterateContextStack.removeFirst();
        }
        return retVal;
    }

    /**
     * iterate context is removed here from the stack when iterate tag is finished being
     * processed
     * 
     * @return the top element on the context stack
     */
    public IterateContext peekIterateContext() {
        IterateContext retVal = null;
        if (!iterateContextStack.isEmpty()) {
            retVal = (IterateContext) iterateContextStack.getFirst();
        }
        return retVal;
    }

}

/**
 * 
 * This inner class i used strictly to house whether the 
 * removeFirstPrepend has been used in a particular nested
 * situation. 
 * 
 * @author Brandon Goodin
 */
class RemoveFirstPrependMarker {

    private boolean removeFirstPrepend;
    private SqlTag tag;

    /**
     * 
     */
    public RemoveFirstPrependMarker(SqlTag tag, boolean removeFirstPrepend) {
        this.removeFirstPrepend = removeFirstPrepend;
        this.tag = tag;
    }

    /**
     * @return Returns the removeFirstPrepend.
     */
    public boolean isRemoveFirstPrepend() {
        return removeFirstPrepend;
    }

    /**
     * @param removeFirstPrepend The removeFirstPrepend to set.
     */
    public void setRemoveFirstPrepend(boolean removeFirstPrepend) {
        this.removeFirstPrepend = removeFirstPrepend;
    }

    /**
     * @return Returns the sqlTag.
     */
    public SqlTag getSqlTag() {
        return tag;
    }

}